基于系统熵变特征分析的电网关键线路辨识方法

针对电力系统线路故障对系统的冲击与系统对故障消纳的耦合动态行为，提出了基于电力系统熵变特征分析的关键线路辩识模型。定义了考虑系统结构与状态变化特征的电力系统熵变及其数学表达，包括基于线路热稳容量裕度变化情况的线路功率裕度熵变（正熵流）和基于系统对故障冲击能量消纳能力的线路潮流冲击熵（负熵流）；建立了基于系统熵变模型的关键线路辨识思路及流程，并给出了基于后评估检验的线路关键性校验指标。最后，通过IEEE-39节点系统和IEEE-118节点系统仿真计算分析，验证了所提思路和模型的合理性和有效性。

Identification of Critical Lines in Power System Based on Analysis of Entropy Variation Characteristics

Targeting the impact of transmission line faults on power system and coupling dynamic behavior caused by the faults， the paper proposes an identification of critical line model based on the analysis of entropy change characteristics of the power system. The entropy change and its mathematical expression is defined for the power system considering the characteristics of system structure and state change，including the entropy change of line power margin （positive entropy flow） based on the change in thermal stability capacity margin and the impact entropy of line power flow （negative entropy flow） based on the system’s ability to absorb the fault impact energy. The thoughts and process of the critical line identification is established based on the system entropy change model， and the critical calibration index is given based on post evaluation test. Finally，the simulation results of IEEE 39-bus system and IEEE 118-bus system verify the rationality and effectiveness of the proposed thoughts and model.